Socket 7

The base 7 is a processor socket for Intel Pentium and pin-compatible processors. It was originally created for the Pentium-150/166, but broke soon after the base 5 as a standard base for slower Pentium CPUs. The base 7 was the last base of the Intel Pentium processors of the first generation. Presumably, in order to escape the enormous pressure of competition, Intel moved with his Pentium II in early 1997 on the slot 1, told the Socket 7 then for entry-level platform, and then finally in 1998 to leave it in the desktop market completely the competition and the Celeron to the new entry-level CPU to explain.

  • 2.1 Socket 7 with split -voltage support
  • 2.2 Super Socket 7


The base 7 had to be "adjusted" in its history several times to the current circumstances. These adjustments but do not relate to the mechanical, but on the electrical compatibility of many motherboards to the large number of CPU models from different manufacturers, which came onto the market between 1996 and 2000. The growing number of new CPUs required at this time on the motherboard increasingly extensive setting options for supply voltage and frequency in the operation of the CPU bus and core. Many motherboard manufacturers recognized the trend and allowed on their products soon settings for CPU models, which were often not even announced. And although the settings were initially not officially documented, many manufacturers submitted the information required for the operation of more modern CPUs according to the support pages of their products and made ​​it possible to operate more modern CPUs on older main boards within the possibilities offered under certain circumstances. A very popular team were, for example, the K6-III/400 AMD and later models from the T2P4 series from Asus.

However, the previously mentioned settings chosen not only on whether a CPU in a motherboard ever ran or even walked permanently stable. The decisive factors were often more constraints, such as the support provided by the BIOS of the motherboard or even the maximum capacity of the built in voltage regulator. So it was quite possible the built in voltage regulator with respect to their electrical characteristics for the high supply currents more powerful CPUs appear to be suitable, but the cooling was not sufficiently specified. Many BIOSes recognize newer or infrequently used CPUs incorrect or - even worse - could this not internally configured such that they were able to reach their full performance potential. Sometimes a team of CPU and motherboard was also short, and to finally refuse during the Power- On Self-Test of no obvious reasons to continue the boot process. In such problems could normally only a newer BIOS version from the motherboard manufacturer for help - if this ever offered such. For motherboards which vendors offered no support, upgraded technology enthusiast, this lack of skills partly in the BIOSes on so-called unofficial patches and even after, for example, for the K6 3 processors.

Clock frequencies

According to the specification of the base 7 allows clock frequencies of 50, 60 and 66 MHz. Officially, Intel has also never supported more than 66 MHz. Many motherboards also allowed the setting of clock frequencies higher than 66 MHz, although the chip sets used were often not specified for it. In particular Intel 430HX chipset often also allowed to operate with up to 83 MHz bus clock. Since this chipset, the clock ratio between PCI and CPU bus was preset to 1:2, even the PCI bus is overclocked at this frequency, but what was the system stability sometimes detrimental. The memory interface then worked out of specification.

As of 1996, Intel slipped more and more control of the base 7 Competing chipset manufacturers began to specify their products for bus clock beyond 66 MHz and to support asynchronous modes of operation, in order not to run the PCI bus and memory interface outside the specification must. In addition, there were always more compatible CPUs; about the K5, AMD and Cyrix 6x86 of. Some of these were the Pentium in some applications quite hold a candle and later underachieve even only at bus clocks of more than 66 MHz. This development eventually led to what is known today as Super Socket 7 and to the fact that the base 7 was increasingly unattractive for Intel.

Operating voltages

Messengers base 4 and base 5 is still very limited options when setting the operating voltages and based it solely on the needs of Intel CPUs, the situation overflowed the base 7 by the increasing diversity Pentium-compatible CPUs proliferating. The CPUs of many manufacturers were no longer supply voltage compatible with the Intel CPUs and had by motherboard manufacturers are taken into account through a variety of settings. Even more complex was the matter by split - voltage CPUs with two supply voltages.

Variants of the base 7

A widely held view is that the base 7 from its predecessor, the base 5, through the support of Split - voltage CPUs (such as the Pentium MMX) is different, in which core and bus interface can be operated with different supply voltages. However, the Socket 7 Socket from 5 different at first only by the presence of another, later, two other so-called BF pins. For details, can be found in the description of the base 5

Socket 7 with split -voltage support

In early 1997, Intel introduced the Pentium MMX processor before one who needed two supply voltages. Instead of re- name the new " base type" ( the base itself mechanically compatible with the base 5 ), Intel left it at called Socket 7 From now on, always had to be to say whether a Socket 7 with or without split -voltage support was talk.

Super Socket 7

The Super Socket 7 is a mechanically and electrically compatible extension to the specification of Socket 7 with split -voltage support. Basically, the timing for the signals of the bus interface are only adapted such that this could also be operated at 100 MHz. Since Intel has this extension is not specified or supported, the manufacturer of motherboards for the Super Socket 7 chipsets from Intel 's competitors were dependent. Popular Super Socket 7 chipsets are the Aladdin V ALi and MVP3 of VIA Technologies.